[PATCH v4 3/5] media: atmel-isc: Enable the clocks during probe

From: Wenyou Yang
Date: Mon Oct 09 2017 - 22:50:53 EST


To meet the relationship, enable the HCLOCK and ispck during the
device probe, "isc_pck frequency is less than or equal to isc_ispck,
and isc_ispck is greater than or equal to HCLOCK."
Meanwhile, call the pm_runtime_enable() in the right place.

Signed-off-by: Wenyou Yang <wenyou.yang@xxxxxxxxxxxxx>
---

Changes in v4:
- Move pm_runtime_enable() call from the complete callback to the
end of probe.
- Call pm_runtime_get_sync() and pm_runtime_put_sync() in
->is_enabled() callbacks.
- Call clk_disable_unprepare() in ->remove callback.

Changes in v3: None
Changes in v2: None

drivers/media/platform/atmel/atmel-isc.c | 34 ++++++++++++++++++++++++++++----
1 file changed, 30 insertions(+), 4 deletions(-)

diff --git a/drivers/media/platform/atmel/atmel-isc.c b/drivers/media/platform/atmel/atmel-isc.c
index 5f8228fc9c8d..a44a66ad2c02 100644
--- a/drivers/media/platform/atmel/atmel-isc.c
+++ b/drivers/media/platform/atmel/atmel-isc.c
@@ -389,8 +389,14 @@ static int isc_clk_is_enabled(struct clk_hw *hw)
struct isc_clk *isc_clk = to_isc_clk(hw);
u32 status;

+ if (isc_clk->id == ISC_MCK)
+ pm_runtime_get_sync(isc_clk->dev);
+
regmap_read(isc_clk->regmap, ISC_CLKSR, &status);

+ if (isc_clk->id == ISC_MCK)
+ pm_runtime_put_sync(isc_clk->dev);
+
return status & ISC_CLK(isc_clk->id) ? 1 : 0;
}

@@ -1866,25 +1872,37 @@ static int atmel_isc_probe(struct platform_device *pdev)
return ret;
}

+ ret = clk_prepare_enable(isc->hclock);
+ if (ret) {
+ dev_err(dev, "failed to enable hclock: %d\n", ret);
+ return ret;
+ }
+
ret = isc_clk_init(isc);
if (ret) {
dev_err(dev, "failed to init isc clock: %d\n", ret);
- goto clean_isc_clk;
+ goto unprepare_hclk;
}

isc->ispck = isc->isc_clks[ISC_ISPCK].clk;

+ ret = clk_prepare_enable(isc->ispck);
+ if (ret) {
+ dev_err(dev, "failed to enable ispck: %d\n", ret);
+ goto unprepare_hclk;
+ }
+
/* ispck should be greater or equal to hclock */
ret = clk_set_rate(isc->ispck, clk_get_rate(isc->hclock));
if (ret) {
dev_err(dev, "failed to set ispck rate: %d\n", ret);
- goto clean_isc_clk;
+ goto unprepare_clk;
}

ret = v4l2_device_register(dev, &isc->v4l2_dev);
if (ret) {
dev_err(dev, "unable to register v4l2 device.\n");
- goto clean_isc_clk;
+ goto unprepare_clk;
}

ret = isc_parse_dt(dev, isc);
@@ -1917,7 +1935,9 @@ static int atmel_isc_probe(struct platform_device *pdev)
break;
}

+ pm_runtime_set_active(dev);
pm_runtime_enable(dev);
+ pm_request_idle(dev);

return 0;

@@ -1927,7 +1947,11 @@ static int atmel_isc_probe(struct platform_device *pdev)
unregister_v4l2_device:
v4l2_device_unregister(&isc->v4l2_dev);

-clean_isc_clk:
+unprepare_clk:
+ clk_disable_unprepare(isc->ispck);
+unprepare_hclk:
+ clk_disable_unprepare(isc->hclock);
+
isc_clk_cleanup(isc);

return ret;
@@ -1938,6 +1962,8 @@ static int atmel_isc_remove(struct platform_device *pdev)
struct isc_device *isc = platform_get_drvdata(pdev);

pm_runtime_disable(&pdev->dev);
+ clk_disable_unprepare(isc->ispck);
+ clk_disable_unprepare(isc->hclock);

isc_subdev_cleanup(isc);

--
2.13.0